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Biomedical subjects

Iu D Starodubtsev

Publications and source records attributed to Iu D Starodubtsev.

10 recordsLinked to original sources
PubMedDate not supplied

[The formation of a complex habit in Black Sea bottle-nosed dolphins under free-choice conditions].

In experiment situation was created of "free choice", which was characterized by the reinforcement of any succession of bottle-nosed dolphin action on the manipulators, placed in the open-air cage under the condition of pressing three definite levers in the required order independently of the number of "superfluous" reactions before and between necessary actions. In the first series of the experiments with eight above-water levers no succession of actions leading to the reinforcement was formed in the bottle-nosed dolphin [correction of aphaline]. In the second series with eight under-water manipulators--both experimental dolphins regularly reached the reinforcement. Stereotype trajectories of movements in the cage were formed, which included swimming past the levers and successive actions on them. Minimum chain of motor reactions was not formed, though some of "superfluous" levers were not pressed. At solving the task efferent generalization in dolphins in both series of experiments was manifested in two ways: the animals reacted in different ways on one and the same manipulator and pressed different levers.

Animals↗
PubMedDate not supplied

[The capacity of bottle-nosed dolphins for generalization according to a relative sign].

In bottle-nosed dolphins by a new modification of previously suggested method, a conditioned reflex was elaborated and consolidated to a relative spatial sign--choice of always left object from two similar ones in conditions of a permanent change of place of this pair of stimuli against the background of one of the sides of an open-air cage. Specialization of the reflex was checked by presentation of a pair of stimuli under different changes of surroundings, including discordance of external orientors and also the way of stimuli presentation. Then the initial objects were substituted by others (12 pairs of stimuli) sharply differing from the initial ones by the form, size, material etc. Retention of adequate choice also at the change of the medium of stimuli presentation, testified to the ability of dolphins of abstraction and generalization by relative sign, i.e. at the choice from two objects of the type "to the right--to the left in general".

Animals↗
PubMedDate not supplied

[Generalization by the relative sign of "top" in bottlenose dolphins].

Bottle-nosed dolphins demonstrated the ability to distinguish the top position of the objects in the process of learning. They always chose the top object from the three identical things under conditions of permanent location changing of this stimulus triplet on one of the sides of the water enclosure. Specialization of the reflex was tested under conditions of the stimulus triplet administration at the background of different situational changes in surroundings, including the changes in location of external reference points. The animals retained the adequate reaction also after a sudden substitution of the initial stimulus objects for others which were considerably different from the initial stimuli in the shape, material, size etc. When the natural stimuli (three fishes) were presented of the number of the stimuli was substituted from 2 for 5, nevertheless, the dolphins chose the top stimulus. The findings testify to the capability of dolphins for generalization by the relative sign "top position".

Animals↗